Method of making fan belts



Fel 10, 1942- w. E. HAGGAN L I 2,272,383

METHOD 0F MAKING FAN BELTSV Filed July 22, 1938 ggf . l A 2 4* 2f VN.

f w Vl 24N ATTORNEY Patented Feb. 1o, 1942 METHOD oF MAKING FAN BELTSWilliam E. Haggan, Barberton, Ohio, assignor to The Firestone Tire &Rubber Company, Akron, Chio, a corporationof Ohio Application July 22,1938, Serial No. 220,729

. 3 Claims.

This invention relates to belts, more especially `to methods andapparatus for manufacturing fan belts and to the fan belts produced.

Customarily in the manufacture of small belts, such as fan belts, aplurality of belts are simultaneously built upon a drum from sheets ofmaterial. In this mass production the reenforcing cord for the nishedbelt is uniformly Wrapped around the drum with the convolutions of thecord being immediately adjacent. Thereafter the individual fan belts arecut from the cylinder of material built. upon the drum and certain ofthe cords are cut and/or exposed. This necessitates covering the fanbelts prior to their use for otherwise the cords rapidly fray out fromthe fan belt and destroy its usefulness.

One object of this invention is to overcome the foregoing and otherdisadvantages attendantv the use of known methods and machines for ymanufacturing fan belts and, to provide a novel,

easily practiced method of constructing fan belts, which methodeliminates construction costs of the prior art.

Another object of the invention is to produce abelt in which thereenforcing cords therein are totally embedded in the body of the belt.

Another object is to provide belts which are resistant to transversecompression and circumferential elongation while also' being suitablyexible circumferentially.

Another object is to provide apparatus for positioning a vpredeterminednumber of cords immediately adjacent each other and then skip anappreciable space prior` to depositing a second set ofadjacent cords.

The foregoing and other objects are achieved by placing a layer of beltstock upon a collapsible form and winding spaced sets of convolutions ofreenforcing cord upon the belt stock. These cords are covered with morebelt stock and the individual belts are cut from the form at the portionof the stock between the sets of convolutions of cord. This cuts and/orexposes portions of the reenforcing cords, which portions are -securedin the belts in any suitable manner in the process ofv constructing fanbelts, with a portion of the belt stock plies cut away;

Figure 4 is a perspective view ol a portion of the finished fan belts;and e I Figure 5 is a detail elevation of the cam means after arcuatemovement of the cam with relation to the cam plate has occurred.

Referring specifically to the drawing, a frame I0 is provided to supportand journal a threaded shaft II. The threaded shaft I I is driven by anysuitable means, not shown, which connects thereto at the clutch I2. Athreaded sleeve I3 having an annular flange I4 intermediate its endsengages with the threaded shaft Il and thereby is driven across thethreaded shaft II by the shafts rotation. A second, or keyed, shaft I5carrying a key I6 is also journalled in the frame II). This shaft I5isdriven in the same direction as the threaded shaft II and at apredetermined relative speed thereto through a gear I'I on the threadedshaft. This gear engages with a gear I8 on a shaft I9 which isjournalled in a gear positioning arm 2|. The arm 2| is rotatably carriedby the .threaded shaft whereby the relative position of the shaft I9andthe keyed shaft I5 can be varied as desired. The movement of theshaft I9 is limited byy an arcuate slot 22 in which the shaft isreceived. A gear 23 is also carried by the shaft IS and it engages witha gear 24 on the keyed shaft I5. By varying the position of the shaft I9inthe slot 22, varying sized gears may be substituted for the gear 23 todrive thekeyed. shaft I5 at a desired relative speed through'thethreaded shaft II, and the shafts may be disengaged b'y such arcuatemovement, when desired. In all events, the shaft II is driven apredetermined number of complete process of constructing the belts `toprevent them from protruding from the finished belt whereby a belthaving the reenforcing cords totally embedded therein can be produced.

In the accompanying drawing;

Figure 1 is an elevation of apparatus for practicing the invention;

Figure 2 is a detail elevation takeny on line 2-2 of Figure 1;

Figure 3 is an elevation of a drum used in the `erally on the shaft.

revolutions faster than the shaftv I5 for a purpose later to beexplained.`

The keyed shaft I5 carries a grooved sleeve 25 which engages with thekey I B and thereby rotates with the shaft I5 although the keyconnection permits the grooved sleeve 25 to move lat- A substantially Ushaped bracket 26 engages'with the threaded sleeve I3 and the groovedsleeve 25 and is slidably carried thereby with the arms thereof parallelto the shafts II and I5. also slidably carried by the sleeves I3 and 25,being positioned adjacent the forwardv side of the ange I4 with relationto4 its normal movement. The bracket 26 carries -a guide pulley 28 overwhich the reenforcing cord' is led on to the fan belt stock whereby thebracket 26 must be given the intermittent motion required to lay the re-A carriage member 21 is and these means include an annular cam plate 29whch is carried by a base member 3l. The base member 3| is secured tothe ends of the arms of the bracket 26 so that the cam plate 29encircles the keyed shaft I5. A cam 32 is carried by and rotates withthe grooved sleeve 25. The cam 32 is provided with a predeterminednumber of small steps, or notches 33 therein which are progressivelyfarther from the base of the cam, the circuit of the cam being completedby the formation of a large step, or notch therein. In the apparatusillustrated, the cam and cam plate each have four steps therein; Figure1 showing the carn as it initially engages the cam plate, which has acam surface corresponding to the cam 32. A "spring 35 is carried by thevgrooved sleeve 25 between the bracket 26 and the carriagemember 2'I tourgeuthe bracket 26 forwardly with relation to the lateral movement ofthe threaded sleeve I3 and the carriage member 2l associated therewith.

In operation, the threaded `shaft II' drives the threaded sleeve I3laterally at a uniform rate. Simultaneously the keyed shaft I5 is beingrotated at `a fraction of the speed of the shaft II whereby the cam `32is retarding the forward movement of the cam plate 29 and the bracket 26with the threadedsleeve by forcing the cam plate 29 and bracket assemblyin the opposite direction with relation to the lcarriage member 21. Theoam's action prevents the forward movement of the guide pulley 28 frombeing equal to that of the sleeve I3, and compresses the spring 35 forthe spring bears upon the carriage member 2'I which is held againstrearward movement by the flange I4. Then when the large step in the cam324` is in proper i rotative position relative to the cam plate, the

bracket 26 is freed for a substantial forward A movement. Thus thespring 3,5, being compressed by the previous cam action, forces thebracket 26 to jump forwardly relative to the movement of the threadedsleeve. This results in a plurality of reenforcing cords 38 being laidimmediately adjacent each other either intouching relation or slightlyspaced in the fan belt stock, as shown in Figure 3, and then having theapparatus skip an appreciable space prior to again depositing, bywinding, a predetermined number of adjacent cords 38. The sleeve 25offers sufIicient resistance to longitudinal movement on the keyed shaftI5 andthe spring 35 is readily compressible to prevent the spring fromforcing the cam and sleeve 25 forwardly instead of being compressed tothe cams action. v cam plate 29 does exert a slight longitudinal forceon the cam 32 to aid in moving the sleeve 25 longitudinally on the shaftI5. Figure 3 shows that a number of plies of rubber stock 40 are wound,or otherwise placed upon a collapsible drum, or form, 4I prior toplacing the reenforcing cord 38 thereon.

The fan bel'ts are then completed by superimposing at least one ply offan belt stock upon the reenforcing cords. A feature of the inventionresides in the belt stock used for it comprises rubber having countlesssmall fibers 43 embedded therein, the fibers extending transversely ofthe .drum 4I. This stock is readily obtained since in milling,l orcalendering rubberfiber mixtures, the fibers all are positioned inthedirection of passage of the mixture through the mill. Then the milledsheet produced is However, the

enforcing cords, as desired. Cam means are cut transversely and thestrip obtained is positioned on the drum with the fibers 43 runningacross the drum parallel to the axis thereof.

To cut individual V shaped, in section, fan belts from the cylinder ofmaterial prepared on the drum 4I, a V shaped piece of rubber 42 must becut from the cylinder between the sets of reenforcing cords, as shown,Next the drum 4I may be collapsed and the fan belts telescoped fromengagement therewith. Obviouslythe re enforcing cord connecting adjacentsets of cords will be out when the V shaped rubber pieces 42 are formedand the exposed ends 39 of this cord (Fig. 4) should be out o or forcedint the sides of the fan belt prior to vulcanization so that thefinished fan belt has the cords entirely embedded. Cutting the fan beltfrom the drum 4I will expose the ends of a large number of thetransversely extending fibers 43 in the fan belt stock. These ends arehighly resistant to wear so that the cross-section of the fan belt isnot appreciably reduced with extended use.' Thus Vthe fan belt retainsthe same radial position on the V shaped pulley seat in which it usuallyl's received whereby the belt does not rapidly wear loose after beinginitially made taut. The fibers extending transversely of the belt makeit quite resistant to sidewise bending and transverse compression, butdo not stiien the belt to circumferential bending, which is an essentialproperty of the belt. The reenforcing cord is stretched prior to beingwound upon the drum 4I so that it maintains the circumference of the fanbelt constant. The resistance to transverse compression obviates thetendency for the belt to be squeezed to a narrower width as it passesover a V pulley, and thus avoids undesirable apparent lengthening orstretching in a circumferential varied by changing the relationship ofthe cam plate and cam. and by varying the relative rotation of theshafts II and I5 and, preferably, the number of notches in the cams. Thespacing between the sets of cords can also be controlled in this mannerand by the pitch of the threads out on the shaft I I'.

Figure 4 shows a fan belt when it is completely assembled and indicateshow a set of seven cords are deposited immediately adjacent and then aspace is skipped prior to depositing the second group of cords.

An overrunning clutch 45 is connected in the shaft I5 to prevent it fromrotating when the shaft I3 and bracket 26 are returned to their startingpositions by reversing the rotation of the shaft II.

Sometimes it may be desirable to cut the reenforcing cord extendingbetween the sets of convolutions before the cord is covered withrubber.A

Then the ends of the reenforcing .cord would be secured immediatelyadjacent, or contacting, the sets of oonvolutions before covering thereenforcing cords with the next ply. In all events, the inventionprovides apparatus by which reenforcing cords can be deposited in fanbelt stock in sucha manner that fan belts having reenforcing cordsentirely embedded therein can be produced. y

In accordance with the patent statutes, I have illustrated and describedthe structure and method of constructing an embodiment of the invention.However, it will begunderstood that various modifications can be madeWithout departing vfrom the scope of the invention as defined inenforcing cords, separating the bands to expose the appended claims.

I claim:

1. In a process for manufacturing belts, the steps of placing a layer ofbelt stock upon a collapsible drum, winding spaced sets of adjacentconvolutions of a continuous reenforcing cord upon the surface. of thebelt stock, superimposing belt stockupon the reenforcing cords, cuttingthe built up belt stock into a plurality of annular bands at the portionof the belt stock between the sets of convolutions of reenforcing cords,and inserting the exposed portions of the reenforcing cords into thesides of the annular bands whereby a belt having reenforcing cords ytotally embedded therein can be made.

2.*In a process for manufacturing belts, the steps of placing a layer ofbelt stock upon a collapsible drum, winding spaced sets of adjacentconvolutions of a continuous reenforcing cord upon the surface of thebelt stock. superimposing belt stock upon thefreenforcing cords,thereafter cutting the built up belt stock into a plurality of annularbands at the portion of the belt stock between the sets of convolutionsof rea portion of the cord originally'extending between t-he sets ofconvolutions-thereof and cutting off the vexposed portions of thereenforcing cords whereby a belt having reenforcing cords totallyembedded therein can be made.

3. In a process for simultaneously manufactui ing a plurality ofreenforced belts upon a coilapsible smooth surfaced drum, the steps ofapplying a sheet of belt material to the drum, winding spaced sets ofadjacent convolutions of a continuous reenforcing cord upon the drum,cutting the reenforclng cord connecting the sets of convolutions,securing the ends'of the reenforcing cord immediately adjacent the setsof convolutions thereof to form a circumferential space which has nocords thereon. covering the sets of convolutions of reinforcing cordwith a rubber sheet to form a laminated cylinder of belt material, andcutting the cylinder into individual bands at the portion thereofbetween the sets of reinforcing cords whereby a belt having reenforcingcords totally embedded therein can 'be produced.

WILLIAM E. HAGGAN.

